Find the Shared Starting String
Company: Google
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: easy
Interview Round: Other
### Problem
Given a nonempty array `words` of strings, return the longest string that occurs at the start of every array element. If the strings have no nonempty common prefix, return `""`.
A prefix starts at position `0` and uses consecutive characters. Any array element may itself be empty.
Preserve the original `longestCommonPrefix` interface: one array of strings and a string result.
### Examples
**Example 1**
```text
Input: words = ["interact","internet","internal"]
Output: "inter"
```
The first five characters agree. The next position differs between `"interact"` and the other two strings.
**Example 2**
```text
Input: words = ["sun","moon"]
Output: ""
```
The first characters already differ.
### Constraints
- There are between `1` and `200` strings.
- Every string has length from `0` through `200`.
- Nonempty strings contain only lowercase English letters.
Overview: Find the longest starting string shared by every array element, including inputs with empty strings or no nonempty common prefix.